Number of permutations p of [n] whose absolute differences between consecutive elements yield up-down sequences.
A348534
Number of permutations p of [n] whose absolute differences between consecutive elements yield up-down sequences.
Terms
- a(0) =1a(1) =1a(2) =2a(3) =2a(4) =8a(5) =20a(6) =82a(7) =326a(8) =1678a(9) =8776a(10) =54804a(11) =357910a(12) =2646340a(13) =20551986a(14) =176420758a(15) =1586656630a(16) =15504954504a(17) =158675287132
External references
- oeis: A348534